Life Gears Academy Adult Programming Classes

27 April, 20:59, by EvaB

These will be at  Diyode Community Workshop, at 71 Wyndham St. S,  conducted by Life Gears Academy in May and June this year.  If you are interested, the link to their site is here:  https://www.lifegears.org/adult-classes

Adult Classes

We are now offering courses for adults to allow them to develop various skills mainly in the field of Computer Sciences. Please look below for our crash courses. Adult classes refer to anyone who is 18 or older.

Intro to Programming

Runs Saturdays 11am to 1pm at Diyode (71 Wyndham St S, Guelph) for May 5,12,26, and June 2,9,16. $120

This would be taught in either python or c (no previous knowledge needed), and would cover the topics below.

Unix and basic CLI, values and types, variables, user input, conditional statements, control structures (loops), functions/subroutines , recursion, and a basic intro to file systems.

Register here.

SQL

Runs Saturdays 1:30am to 3:30pm at Diyode (71 Wyndham St S, Guelph) for May 5,12,26, and June 2,9,16. $120

Databases would be using MySQL and this course would cover the following.

Basic CLI for MySQL only, what is an RDB?, why do we use MySQL and its cousins?, standardization and why it helps, how a database is structured, permissions and users, database commands, tables and values, table commands, select, update, delete, drop (DANGEROUS), sub queries , variables (brief), and how SQL can be used in a job.

Register here.

 

 

Makerspace Jobs

24 April, 20:22, by EvaB

Makerspace Assistant (Part-Time, 12 Month Contract)

Idea Exchange, Old Post Office


Are you constantly tinkering to discover how things work? Do you have a passion for mechanics and get excited about new technology? Do you enjoy sharing your knowledge and findings with people who share your passion? Idea Exchange is seeking a talented and creative Makerspace Assistant for our brand new location, the Old Post Office. Does this sound like you?

As a Makerspace Assistant, you will plan, organize and conduct makerspace programming for members as an extension of your knowledge and passion for all facets of technology. You will act as the makerspace expert by training other staff and volunteers on the ins and outs of the makerspace and equipment. Additionally, you will assist with circulation responsibilities and other duties as required.

To be qualified for the role, you will have experience working in a makerspace including troubleshooting and maintaining equipment. Your aptitude for mechatronics, familiarity with small tools and equipment, and previous experience in a service environment is essential as you develop a unique hands-on space where learning takes place. Previous experience with a 3D printer, laser cutter or similar technologies is an asset. Previous training and instructing experience is an asset.  

This is a part-time, 12-month contract position where you will work approximately 24 hours in a bi-weekly period. The position may require work from multiple branch locations within Cambridge. The starting schedule is as follows and is subject to change.

Week 1 Week 2
Monday 1:30 – 5:30 p.m. 1:30 – 5:30 p.m.
Tuesday 5:30 – 8:30 p.m. 5:30 – 8:30 p.m.
Saturday 10:30 a.m. – 5:30 p.m. Off
Sunday 1:00 – 5:00 p.m. Off

 

If you think you are up to the task, please apply by May 7, 2018 to:

Corrine Denbok, HR Specialist
Idea Exchange
1 North Square, Cambridge, Ontario, N1S 2K6
Email: hr@ideaexchange.org
Apply Online: http://ideaexchange.org/about/career-opportunities

 

Makerspace Team Lead (Full-Time, 12 Month Contract)

Idea Exchange, Old Post Office


Are you passionate about mechatronics with the ability to see the broader scope of learning? Are you a natural leader but likes to keep your hands in the day-to-day work? Idea Exchange is seeking a talented and creative Makerspace Team Lead for our brand new location, the Old Post Office. Does this sound like you?

As a Makerspace Team Lead, you will oversee makerspace programming including guiding program creation, delivery, training, and overall program assessment. You will seek and engage community partnerships to enhance future programming. Additionally, you will participate in the day-to-day activities within the branch including assisting in programming and circulation duties.

To be qualified for the role, you will have experience working in a makerspace including troubleshooting and maintaining equipment. Your aptitude for mechatronics, familiarity with small tools and equipment, and previous experience in a service environment is essential as you develop a unique hands-on space where learning takes place. Your exceptional communication skills will be helpful as you quickly build rapport with outside partners and members. Your education will include a post-secondary diploma in Mechanical or Electrical Engineering (or equivalent). Previous training/instructing experience and previous supervisory experience is considered an asset.  

This is a full-time, 12-month contract position where you will work approximately 70 hours in a bi-weekly period. The position may require work from multiple branch locations within Cambridge. The starting schedule is as follows and is subject to change.

Week 1 Week 2
Tuesday 9:30 a.m. – 6:00 p.m. 9:30 a.m. – 6:00 p.m.
Wednesday 12:00 – 8:30 p.m. 12:00 – 8:30 p.m.
Thursday 12:00 – 8:30 p.m. 12:00 – 8:30 p.m.
Friday 9:00 a.m. – 5:30 p.m. 9:00 a.m. – 5:30 p.m.
Saturday Off 10:30 a.m. – 5:30 p.m.
Sunday Off 1:00 – 5:00 p.m.

 

If you think you are up to the task, please apply by May 7, 2018 to:

Corrine Denbok, HR Specialist
Idea Exchange
1 North Square, Cambridge, Ontario, N1S 2K6
Email: hr@ideaexchange.org
Apply Online: http://ideaexchange.org/about/career-opportunities

 

 

 

The Old Post Office is the newest Idea Exchange location. It will be a space for creative minds to gather – to tinker, code, bend, sketch, fabricate and build. A place where the past and future meet because it’s not just about who you are and what you do, but who you will become and what you will discover.

Idea Exchange has transformed into a space where people of all ages can come together to share their passion for art, reading, knowledge sharing, technology, creativity and culture. Our six locations in the community provide endless resources, learning and fun to our members making Idea Exchange a pillar of arts and culture in Cambridge. Want to learn more? Visit us at http://ideaexchange.org.

Please note that this position is open to internal and external candidates. Only those candidates selected for an interview will be contacted. A vulnerable police records check may be required as a condition of employment depending on the nature of the position.

 

Custom Stratocaster

24 April, 20:15, by EvaB

One of our former members, Joel Dube did this fine work.

This is a custom stratocaster build. The top wood is zircote and the back and pickguard are black limba. The sound knobs are made from Indian Rosewood. The neck, electronics and hardware were taken from a Squier affinity series stratocaster.

 

 

 

Training course: Introduction to 3D design and CNC using Fusion 360

23 April, 13:43, by EvaB

One of our members, Cristian Golu, has offered to give a course at Diyode for our members and anyone else that’s interested.

If you are interested, please contact Cristian directly at cristian@3dlinux.com

About Cristian:

He is a mechanical engineer (Welding) with a passion for electronics. He has 20 years of experience Canada.

Training course: Introduction to 3D design and CNC using Fusion 360

Description: In this course the students will be introduced to Fusion 360: Model and CAM. The students will learn how to create a sketch, model a 3D part, create a paper drawing and create a CNC Gcode file.

Diyode is Looking For a New Home

09 January, 20:33, by EvaB
Diyode Community Workshop has served the community of Guelph since 2010.  We provide tools, space and community for people interested in woodworking, metalworking, electronics, prototyping and all sorts of other making.

We knew that this time would come, but it is finally here. Diyode needs some help, and we’re hoping you folks out in internetland might have some insight. Our current home is going to be torn down and redeveloped in the next few months. We need to find a new home where we can flourish and continue to serve the community.

We’ve been in our current location since we started over 7 years ago, and have built our community workshop into one of the most successful makerspaces in Canada. In our time here, we have helped all sorts of local organizations with building projects, parade floats, prototyping expertise and other resources. We have helped local businesses like Grey Rock Co, Children’s Art Factory, Science and Sons, and Fantescapes launch their businesses and build the items they need. Four of our members have built homes for themselves at Diyode through tiny homes, yurts and bus conversions.

As a group, we have built innovative new tools for teaching electronics and programming to kids, and travelled to many schools in the area, introducing kids in grades 3 through 7 to the joys of coding. And we have built tools in the shop to help people in third-world countries, most recently installing a plastic recycling system in a community centre in Haiti.

We have done all this with funding only from our membership fees, a few grants, and sales of our projects. This was possible, in part, because we had a decent space at a very reasonable price. We hope to keep up this level of awesome, but to do so, we need to find a stable home at a sustainable price.

We are looking for a light industrial space between 2000 and 5000 sqft, ideally less than $10 / sqft / year.  Being near downtown or on a bus route would be ideal, as we have many lower-income members without their own transportation.

This is our list of need and wants:

Must Haves:

  • Light Industrial space
  • >2000 sqft
  • < $14 / sqft / year
  • Concrete pad in some of the space for metal shop
  • 100 Amp 2 phase power
  • Washroom
  • Centrally located or on bus route
  • At least 6 parking spots

Nice to haves:

  • 3 phase power
  • >3000 sqft
  • < $10 /sqft / year
  • Bay door
  • spray booth (smaller)
  • clean drying room with intermittent exhaust fan for stained/finished wood projects
  • office area with separate entrance and bathroom for multi-age multi-discipline classroom area
  • Metal shop are to be twice as big (?)
  • Separate entrance to “clean area” with separate washroom for public/ children/ tasks involving clean, safe, well lit working space. (addresses many needs, including increasing the percentage of women / special needs / other members of community not served at present)
  • Parking for up to 20

If you know of any spaces, or anyone who might be able to help us in our search, your help would be forever appreciated.

Thank you for your help, from all of us at Diyode.

 

Diyode Design Competition

01 August, 15:46, by EvaB

Launch Party!!

21 June, 20:27, by EvaB

 

This past Monday, we celebrated our new membership with Community CarShare  and the launch of the new Toyota Tacoma pickup truck in its own parking area at our location.

 

Diyode and the community at large will benefit from the use of the truck, as well as the rest of the fleet of vehicles managed by CarShare.  The Tacoma has a home on the paved pad outside of Diyode, and can be easily seen and accessed from Wyndham street South, just south of Wellington Street, where Diyode and several other businesses are housed.

…………………………………………………

 

 

 

                   About Community CarShare

Community CarShare is a non-profit co-operative which provides its members access to vehicles on a self-serve, pay-per-use basis. The co-operative was founded in 1998 and operated first in Kitchener-Waterloo, adding service to Hamilton in 2009, Elmira, Guelph and St. Catharines in 2013, and London in 2014.

Community CarShare’s mission is to deliver a carsharing service which empowers people to make affordable and sustainable transportation choices.

Community CarShare currently has more than 1900 members who have access to a fleet of 60+ vehicles, stationed along main transit corridors.

Haiti – Ruminations

15 February, 15:49, by Simon Clark

See Also: Haiti: Lessons Learned in Plastics

I recently had the opportunity to head to Haiti, part of an effort to build a small scale recycling operation in the town of Jacmel. I’ll deal with the success or failure of the machines in another post, but here I wanted to get down some of my impressions of the trip as a whole, especially from the perspective of a first world maker.

We landed at the Port au Prince International Airport at around 3pm.  My cousin, Sarah, met us at the airport, and we went about the task of collecting our bags. We were travelling with a group of 12 people. My focus was entirely on the plastics project. The others are helping Sarah with other aspects of her work down here. Some of this work is at the home where she fosters between 3 and 5 kids at any given time. There is also a clinic where she leads a group of Haitian midwives assisting with births, pre and postnatal care, or education. Lastly there is a house, dubbed the OliveUs House, that our group has rented to house the midwives and women in need of a place to stay to get back on their feet.

With twelve people in the group, we had a lot of bags. I can only take credit for 3 or so. I brought a lot of plastics recycling bits, and a good haul of tools to use down here and leave when I head home. The rest of the bags are filled with clothes, prom dresses, cloth diapers, maternity pads, sewing machines and a plethora of other items. It’s a 3 hour trip over the mountains into Jacmel. We had a 3 ton flatbed truck belonging to Sarah to take the luggage, and a hired van to take the people.

The trip over the mountains was uneventful, for the most part, but it is hard to not notice the poverty around us, especially in the outskirts of the capital. Garbage is everywhere. People are everywhere, often on top of the garbage. Street dogs hunting for missed morsels of food compete with pigs and chickens, set loose in the mess to fend for themselves. Higher in the mountains, dusk, then full on dark greeted us, but the streets are still full of people. They are fetching water in jerry cans, deftly hopping out of the way as our driver rocketed us past. When we slow down for a speed bump, we hear thumps on the car panels as people hop on or off the back of the van, to shorten their walk. Those that aren’t out walking are clustered around the occasional light source, or sitting on the guard rail, watching us pass, or busy on their phones. With no power in the grid, the night is extremely dark.
We reached our destination at around 7:30, well past dark. There, we are introduced to Jean Moise Michel Jacmel, nine months old, HIV+, and severely undernourished and dehydrated. Moise was abandoned at the Jacmel hospital 5 days previously, and was ranking very low on the hospital’s priority list. They were more than glad when Sarah offered to take him home. Two days later, he’s with us at our first dinner in Haiti, and took a turn for the worse. We rushed him to Sarah’s, where she spent the night trying to rehydrate him. We now think he may be lactose intolerant, which could explain his poor health, and why he was abandoned at the hospital. Sarah suspects that perhaps the mother had died, as the malnutrition looks like a recent development. He’s doing better now, more alert and keeping most food down, but his future is still uncertain. It’s a stark reminder of the differences between Canada and Haiti, and how easy it is for life to go pear shaped when poverty is commonplace.

And poverty is everywhere there. In Jacmel, I heard rumours of an upper class somewhere, but I saw no evidence. The most egregious display of wealth was an old Mercedes utility vehicle that had an intact windshield. But despite the lack of resources, I saw very little evidence of crime, of violence, or of desperation. Most people don’t seem unhappy, although I learned that they have seen more than their share of sickness and death. But for the most part they are just getting on with it, and doing it with pride and resilience.

On one of our quieter days, my daughter, Juliet, and I had the opportunity to have lunch at the home of one of Sarah’s previous employees. St Emen is a short, happy woman, living in concrete shack in a field near Jacmel. She proudly showed us her home, quick to mention that she owns it herself. The aforementioned shack is their sleeping quarters, and holds two handmade single beds and an old hospital gurney.  This is where she, her partner, and 3-4 kids sleep. The kitchen is an old USAID tent across the dirt yard. Chickens run around our feet while we consume one of their brethren for our lunch.  There is also a generous helping of rice and beans, and a simple salad, washed with water in a jerry can that was hauled in from a communal tap a few hundred meters away. One day, perhaps, electricity will come to her and her neighbours, but that is a far off dream. After lunch, she goes digging under one of the beds, and comes out with a stack of pictures.
She shows me her 8 children, 5 of whom are still alive. She seems to feel this is an accomplishment, and I don’t know enough to disagree.

Our first full day was spent unpacking the many suitcase,s getting our bearings, and visiting the various sites where our work would be done.  Myself and a couple of my companions scavenged some wood, and built a workbench to assemble the machines on. The day after, I got to work.  Or at least, I tried to. I’d brought as many tools with me as I could, including Diyode’s plasma welder, but these aren’t much use without electricity. Haiti’s power grid is run entirely off of large diesel generators. Typically this are run for a few hours a day, starting in late afternoon and running through until sometime in the middle of the night. What we discovered was that our trip coincided with the lead up to Carnivale, a national party. Seems like they were hoarding the diesel for the party, as the power often didn’t come on at all until after midnight, and was off by the time I woke at 6am.

After a couple of days of struggling with an almost non-existent electrical supply, and a difficulty in acquiring materials, We decided to move the project to the workshop of Travis Knipple of F1 Engineering. Travis is Pennsylvania-born, and moved to Haiti after a number of humanitarian trips. He has a well-stocked workshop, where he builds stuff. Part of his mission is to empower Haitians by teaching them some of his skills, and to that end, he has several associates who he gives full access to his workshop, including lunch each day. These guys get to use his tools, space, and truck, and get jobs from other people in the area, mostly fixing motorcycles, and welding together gates and window bars. This provides them with a decent source of income, and means that when Travis needs help for his projects, he’s got a pool of talent nearby that already knows his tools, and how he works. This crew has a reputation as the best welders in Jacmel.

Before I even met Travis, I saw an example of one way that small ideas can have big impacts. Many Haitians use their phones as a lifeline. Cell service is cheap (I paid $4 for two weeks of service, comparable to what I pay $30 for in Canada).  The phones, however, are mostly cheap imports.  The batteries don’t last. Outside of Travis’s workshop there is a tree with a strip of 16 outlets screwed to it.  The outlets are powered off the grid when it’s available, the generator when it’s on, and solar or battery power the rest of the time. Not once did I see less than 10 people gathered around the shade of their tree, charging their phones, and chatting through the hottest part of the day.

It’s a simple idea with a big impact on the surrounding community. Travis’s relationship with the guys who use his workshop is similarly impressive. Rather than coveting his tools, he is sharing them freely. The wear and tear must be significant, but the skills learned, and the opportunities they create are life changing.

And it was from Travis where my biggest lesson of the trip came from.

I realized that as a maker in North America, we have endless opportunities to be creative, to innovate and build something new and amazing. We have access to the resources to make almost anything that we can imagine. But how often do we have the opportunity to fundamentally change someone’s life for the better? Sure, we build a cool clock, a better 3D printer, an innovative fridge magnet, but imagine figuring out how to build a simple $2 float switch out of available parts (something that could benefit thousands of homes in Jacmel alone), then teaching that skill to someone who could make a career out making and installing them. There are so many opportunities to apply a little bit of ingenuity, and bit of our knowledge of materials, electronics, or fabrication to problems that people around the world are facing every day.

There are a number of stellar examples of this. My mind goes to projects like the Gravity Light, or Joshua Silver’s self adjusting glasses, but my suspicion is that you could throw a group of makers at a place like Haiti, and they’d be hard pressed to not leave the place better than they found it.

Now don’t get me wrong. Being a maker in Haiti can be frustrating. Sitting here in Guelph, I can just order an arduino, RGB LEDs and some hall effect sensors off of amazon, and get started on the next great idea within a day or two. In Haiti, I’d be surprised if you could find any for sale in the whole country. Ordering anything for delivery is more than likely to get lost, if you’re lucky enough to have a n actually address. But the sheer quantity of problems that need a solution, and the potential impact that an ingenious idea could have are vast.

Haiti – Lessons learned in plastic.

15 February, 13:48, by Simon Clark

See also : Haiti: Ruminations

I started this project with a simple goal in mind. Build the 4 machines outlined on Dave Hakken’s Precious Plastic website, then build them again in Haiti. It is said that no plan survives first contact with the enemy, and this story is no different.

When I left Haiti last week, I walked away from one functional machine, one untested machine, and one that barely worked at all. The fourth machine, we didn’t even try. Here I plan on taking an unflinching look at my successes, my failures, and the path that got me to them. Please settle in, this could get long. And boring…

This particular story starts in May, 2016. My cousin Sarah, a midwife in Haiti, discovered the Precious Plastic website, and contacted me to ask if I thought the plans were reasonable, and could work for her. She works with a lot of people in Haiti, trying to find sustainable sources of income. This, she reasoned could be another. My initial response was “I dunno. Let me look into it”, followed a few days later by “I dunno, but let me try”. I presented the plan at a Diyode meeting shortly there-after, and managed to convince a few other people to help. Notably Eva, Brennan, and Liam, who were instrumental in getting the machines as far as we did.

Now, my first mistake was thinking that 8 months was enough time to get these built, using an evening or so a week, and maybe some time on Saturday mornings. I also should have put on my project managers hat at the start, figured out timelines and deadlines, set some milestones, and thrown the whole thing on Trello. But my tinkerer’s heart is weak, and I just wanted to get started. I also had a great deal to learn about the tools I would need to use. The metal lathe and plasma welder would play prominent roles in the project, and I wanted to get more proficient with both.

The Shredder Build

The first machine that I tackled was the shredder, since without the shredder, the other machines just take up space. I decided to work with Hakken’s basic design in metric, meaning that the laser cutting would have to be done outside of North America. No one in North America that I contacted had access to metric thicknesses of stainless steel. I found a company in China that would cut them out, and actually do it cheaper than anything I could get done locally. I adjusted the dxf files to work with stainless steel hex bar stock that was easily available on North America, and we were off to the races. In hindsight, I should have also added mounting holes for the shredder and hopper, as I had to drill these later.

One of my design criteria for the shredder was that I wanted it to be built out of commonly available parts, so that it could be repaired using commonly available parts. In the Precious Plastics build notes, it says “scavenge a motor that runs at 70rpm, and 100N*m of torque”. OF course, scavenging in North America is no longer possible for the most part, and Hakkens gives no indication of what sort of machine this type of motor comes from. I struggled for a while with the best way forward with this. 100Nm is a LOT of torque, but at 100rpm (what I had geared down to), it was achievable with a 1.5HP motor. The motor cost me CAN$300, but can be gotten in the US for US$150.

For gearing, we experimented with several options. In the end, I decided to go with dual v-belts from the motor to a pair of 10″ pulleys. That transfers through a bearing to a pair of 12 tooth bike chain sprockets. The other end of the bike chains are 56 tooth sprockets from a mountain bike, welded to a tube that mates with the shredder head axle. This all made for a fairly complex build, but quite forgiving, in the end. The motor put off enough torque, and the belts and pulleys transferred it well. In the end, the weak points where the generator running the motor (it would cough and sputter when the motor pulled too many amps) and the shear pin between sprocket and the shredder head. The axle broke through every shear pin we threw at it, until we got up to a 3/8″ hardened steel motorcycle bolt. At this point, I was worried that there wasn’t enough stock left on the axle to stand up to the torque, since we had drilled the shear pin hole so big (the axle is 20mm diameter at the point where the shear pin connects, leaving just 5mm of steel on either side of the shear pin). This arrangement seemed to stand up ok, but I did notice there was some deformation of the shaft around the pin after some use, so I am not fully confident it will last forever.

If I had to do the shredder again (and I probably do), I suspect I would bite the bullet and go with an appropriate worm gear. This means lubrication is much more important, and we are no longer dealing in generic parts at all (The worm gear parts would probably cost $100 from somewhere like McMaster Carr), but the build would have been so much easier. I’m still mulling this over, though, and am open to suggestions.

So, now we have a fully functional shredder, except, it still ain’t perfect. You see, bottles have a tendency to just bounce around on top of the shredder teeth. This means pushing on them with something, or stopping the machine and reaching in to re-orient the bottle. Ideally, the shredder should be able to operate with no intervention. Just chew through whatever you put in until it’s done. This, however, was not the case. Also, even at 108 Nm of torque, it still struggled sometime with the hard plastic at the top of the bottles. It’s close to strong enough, and gearing down to 60 or 70 rpm would probably give it enough punch. I tried arranging the teeth in a spiral, a point (a spiral that reverses at the middle point) and randomly. A spiral seems to be optimum for minimizing the bouncing of the bottles. In some cases, a bottle would line up under the teeth, and cause a momentary spike in the required torque, but I am hoping by increasing the torque that little bit, that will address that as well. I am also playing with the idea of putting a heavy flywheel on the motor side of the gearing, but I need a better shear pin set up for that, I think.

The Extruder Build

Oh man, this one gave us some trouble.  And by us, I mean mostly Brennan and Eva, who absorbed much of the stress here.

Our biggest issue, the one that held us up for the longest, was with the extruder screw. We spent a lot of time looking for a screw solution that resembled the screws used in commercial extruder system. Our first option was to get a 24″ long, 1″ diameter fluted masonry bit. The cross sectional profile was good, but it was 2 fluted, and as such had a very aggressive pitch on the fluting. The other issue was that only the carbide on the point of the drill was 1″. The rest of the shaft was somewhere around 7/8″, but not even close to precise. Once we’d cut off the carbide, we were left with something that didn’t really fit into any commercially available pipe.

Our next option (and the one we shipped with) was a 1″ wood auger bit from McMaster Carr. This was precision ground along the whole shaft, fit well inside the stainless pipe, and looked to be quite reasonable. The profile was quite different from what is typically used, but I think it should work. Sarah will be testing it once she has the time and power at the same time. I’ll report back.

What I plan on doing, once I get some time, is create a custom jig for the milling machine that will allow us to machine custom screw profiles out of solid steel rod

For the body of the extruder, we started with stainless pipe, cut out the hopper hole, and welded on plates for the hopper to attach to, and two very hefty feet for it to mount to the frame. For the extrusion nozzle, we didn’t go with the end cap style interchangeable nozzles in Hakken’s designs. Instead we welded a solid plate to the front that we could bolt other plates to. If you go with this design, try to minimize the amount of metal you put on the front, as this will be a significant heat sink, if it is too big.

Another thing that tripped us up is that stainless steel warps very easily while being welded. Much more so than normal steel, it seems. Brennan, an experienced welder, took what he thought were small enough welds on the pipe, but once it cooled and we reinserted the auger bit, it was clearly significantly warped. Brennan was able to bend it back into shape with much effort, but it was not a fun job.

For the electronics on the extruder, we used a 100rpm 12VDC motor from MakerMotor.com, with a digital speed controller, and a 12v DC power supply design for high wattage LED installations. The band heaters were controlled by simple PID controllers bought off of Amazon, that came a solid state relay and K-type thermocouple.

My last lesson learned on this is tho avoid too much mass on the extruder tube. We felt, during the design stage, that the tube should be able to handle high pressures and high torques. We welded extra cladding onto the business end of the nozzle, extremely solid mounting feet, and a heavy front plate.  In hindsight, we may have over-estimated these factors, as this meant that the band heaters really struggled to heat up the tube.

We completed the extruder build on the second last day of the trip, fired it up, and got the auger spinning, and the tube heating, but we didn’t have any plastic pellets ready to put into it.  Then the power went out, and didn’t come back on until after we left for the airport.

The Compression Oven Build

The oven was the one item that I went down with a very ill-formed plan on how I was going to get done. Sarah had told me that she had an old autoclave that could be used for parts, but not knowing what it looked like on the inside, I decided to just wing it. Our preparations in the weeks before leaving had gotten a bit desperate, and I was happy to take the oven off my plate in favour of the other machines.  Plus, I reasoned, it was the simplest build, and the one that most relied on what we would be able to scrounge once we arrived. I was pretty sure I could get it heating with a PID controller and a solid state relay, and that with enough time to throw at it, I could probably pull something off.  So, flying by the seat of my pants, I decided to make most of my decisions down there.  For the compression mechanism, I reasoned that there would be plenty of access to car jacks of one sort or another down there (wrong!). For the oven part, I assumed I would be able to scavenge parts from an electric oven (Oh so very very wrong), and insulation to put around it (holy hell, are we starting to see a pattern here?). I had no luck finding an old car jack. No-one has electric ovens in Haiti.  They are all gas, as the electrical supply is so unreliable. And lastly, Haitians have very little need of insulation, since it doesn’t get cold, and almost no-one has air conditioning. Freezers are everywhere, but not clad in heat resistant insulation, more likely to be styrofoam. Given more time, I may have been able to find an old gas stove to take apart for some fibreglass batting, but alas, time was too short for that.

I was able to get my hands on the old autoclave. This provided a small heating element, and so we built as small an oven as we could. But without insulation, it was radiating heat as fast as I could pump it in, so getting up to temperature was damn near impossible. I’m pretty sure that with a good thickness of insulation, and an outer metal shell, it is much more likely to work well.

My other compromise, which I am also second guessing at this point, was with the compression mechanism. The precious plastics design calls for a car jack underneath the oven. All that I could find on the ground in Haiti was a trailer tongue jack. Since those are designed to be jacked from the top, the only good way to arrange it was with the jack on top of the oven. This means that there is less space between the heating element and the plastic being melted, and probably uneven heat. Jacking from the bottom really is the optimal arrangement.

My plan for compression forms was to make plates and bowls. Before leaving Canada, I bought a variety of stainless steel bowls and enamelled camping plates. These seem like a really good place to start, and Sarah has had some luck getting plastic in them to melt and form, just not with enough heat to get a nice solid shape yet. If I had time, I would also fabricate a custom fitted metal cylinder for each set of forms, to help guide the compression. Having not successfully made anything with the oven yet, take this with a grain of salt.

 

 

Happy Birthday, Liam!!

07 February, 13:49, by EvaB